I would like to purchase a rear scraper blade for a Kubota B7500 (4WD,21hp) tractor but not sure what length to purchase. I will be grading a gravel road with an 8 - 10 degree slope. Can it handle a 6 ft. blade or should I purchase a 5 ft. blade? Also, any source or brand recommendations.

I am not putting you off here, you've mixed measurements. Do you mean 8-10% slope (grade)? or 8-10 degree incline (angle)? Because when dragging a load of gravel uphill, there's a big difference between a 10 percent slope and a 10 degree incline. Example: a hill with a 20% slope is equivalent to an 11 degree incline.

Short of that, matching horsepower to the task is only one consideration when selecting a blade. When you index a rear blade, the scraping width necessarily narrows. You want to select a blade that - when fully indexed - will still scrape a path that's at least as wide as the rear track.

Brand selection on the other hand is a lot less technical. It pretty much boils down to "you get what you pay for". If it helps, I too thought I needed a rear scraper blade for gravel drive maintenance. Turned out to be a big disappointment. Traded the scraper for a boxblade and a landscape rake, and have had much better tended farm roads ever since.

//greg//

Appreciate your reply. Although I am not exactly sure what the difference is between percent slope and degree incline, my best guess is that we have a 8-10 percent slope. My problem with the gravel road is that people spin their wheels leaving holes on the up side and hills on the down side. I need to move the gravel up the hill to fill in the holes that have been created. Is this response any more help?

Correct me if I'm wrong but to me a slope is measured in percentages from 100% slope being straight up and a zero percent being no slope at all?? Soooo, a 50 percent slope would equal a 45% angle??
I may be all wet on the slope vs. percentage thing, BUT.
As Greg said don't bother buying a rear blade, I had one, sold it. They aren't heavy enough to do anything on an already compacted anything. I too then bought a landscape rake, twice as usefull as a blade. Like a blade it won't tear loose anything that is compacted, but for spreading new gravel, loose soil, moving snow, it's got a blade beat seven ways from breakfast. I've even used as they are intended as a landscape rake to clear rocks, roots, etc. Not the magic bullet there either, but lots better than a blade.

Frank.

Yup. I tear down the high stuff with the boxblade - drop the scarifiers if/when necessary - and drag material in bulk through the low spots. When the coarse work is done, I swap the boxblade for the landscape rake and procede with the fine work; level the whole thing side to side, then end to end. A lot easier/faster/prettier result than wasting time with a rear scraper blade.

Thanks for all of the feed back. I'm now convinced a box scraper is the way to go. Will a 21hp 4WD Kubota pull a 5' box scraper or ahould I look for a 4'. Sorry, but I'm new to this business.

Again, selection should be based upon tires. If your tractor footprint is less than 48", get a four footer. It's more consistent with the horsepower rating. But if the footprint is between 48" and 60", get the five footer. You'll soon learn how big of a bite that 21hp will handle.

//greg//

My contrarian opinion is that dollar for dollar, your best investment is a rear blade. It's light to handle, inexpensive, can be used some in reverse, and doesn't have high traction demands. While the gannon is much better for cutting/scraping and pulling large volumes forward, a blade is better for moving loose material laterally.

Your hitch likely doesn't have power-down, so you may want to attach a supplemental weight. If you have to dismount with a wrench to adjust "one-side-higher," you can replace one of the vertical hitch arms with a crank one that lets you make this adjustment from the seat.

Most of the use-time the blade will be angled rather than perpendicular to the tractor. The angling also lets you control the effective width to some extent (as in squeezing through a gate). It should be wide enough that at maximum angle it at least covers the tractor track.

I have a NH tc33d and have a rhino 7' blade which is 2' wider than the tractor. I grew up using a rear blade on the back of Ford 8n's and 801 tractors. I mainly use them for snow but have spread dirt and gravel too. When I got a 15 yard load of gravel for my drive, the rear blade didn't work as good as I wished. I either had it too high or it dug in too much. After I got the gravel spread out pretty good, I hooked on to a large, heavy duty wood skid, through on a bunch of weight, and pulled that up and down the drive. I could move the chain more to one corner so the skid angles and moves the gravel to one side. I'm not saying the skid idea is the way to do it, but it did have the ability to shave the high spots and deposit the gravel to the low spots. All conditions are different so don't buy until you know what you need. good luck.